getChildrenNames

Returns an unmodifiable set of relative children names (strings), or
returns null if the parent node is not found or if no children are found.
This is a fairly expensive operation, and is assumed to be performed by
browser applications. Calling this method as part of a run-time
transaction is not recommended.

put

Stores a map of key-values for a given FQN, but does not delete existing
key-value pairs (that is, it does not erase).
Intended to be used in a non-transactional environment, but will use
auto-commit in a transactional environment.

prepare

If onePhase is true, commits the transaction; otherwise, associates
the txn value with the transaction and expects commit() or rollback() to
be called later with the same tx value. Performs retries if necessary to
resolve deadlocks.